PairGain 150-458-100-05, Руководство пользователя

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150-458-100-05 Overview
HRE-458 List 1, List 1B, and List 2 February 23, 2000 3
Air-filled Stub Unit
The air-filled cable stub on the List 2 unit ( Figure 2 on page 4 ) is equivalent to an ALP FTS-PIC air core telephone
cable (refer to Table 5 on page 27 for a complete description of the cable stub). The air-filled unit is intended for
buried, aerial, and duct applications. Standard color codes are used for pair identification with color compounds
chosen for electrical balance and permanency. An inner jacket protects the core and provides improved
mechanical and electrical characteristics. The outer jacket provides protective covering that can withstand
exposure to sunlight, atmospheric temperatures, ground chemicals, and stresses expected in standard installations.
Air-filled Stub Pressurization
The unit has an internal pressure cutoff valve, air intake stem, and pressure relief valve. The air cutoff valve is
used to shut off the inlet air supply that is pumped from the main feeder cable through the 30-foot (9.144m) stub
into the HRE-458 enclosure.
• To shut OFF the inlet air supply, turn the air cutoff valve clockwise one full turn.
• To turn ON the inlet air supply, turn the air cutoff valve counterclockwise one full turn.
P
RESSURIZED
A
PPLICATIONS
For pressurized applications on the HRE-458 List 2, the Schrader air stem valve is used. A pressure gauge is
attached to the valve for the purpose of measuring the internal pressure of the enclosure. This valve is also used
to relieve the internal pressure prior to opening and removing the dome cover. This can be done by depressing the
center pin on the valve (see
Figure 2 on page 4 and Figure 3 on page 5 for air stem valve and pin locations).
The cable complies with the requirements of ANSI/ICEA S-85-625-1996 and REA PE-22.
Depressurizing must be performed every time the cover is removed from either enclosure.
Failure to do so may cause personal injury or damage to the equipment.